isola96

?... I think joe has it spot on.... No?

samfloor

No!!!!!!!!!!!!!!!!

__________________
[url]http://www.flooringforum.com/forum/[/url]

isola96

Dude that stuff is easier putting down then P&S you can't mess it up I prefer laminate interlocking but that's me but on a slab you need to use a underlayment barrier like that.

joecaption

Ok so where did I go wrong? We all have something to learn here, so help me out with better info for this poster.

samfloor

It is never a good idea to put plywood on a concrete floor. Every hole the tapcons make will allow moisture to come thru and cause the plywood to rot. Every time I have seen plywood put on concrete it has failed.

__________________
[url]http://www.flooringforum.com/forum/[/url]

joecaption

And what would you suggest? If it's 1/4 tile board that's not water proof and may act like a sponge since you could not lay down a vaper barrier and thin set it in place.
I've done a few dozen of them in my area including my own slab home that the slab sets below grade (and it's got a really high water table) by sealing the floor, adding a 6 Mil. vaper barrier, use 1-1/2 Tap-Cons (The slabs going to be 4" thick) and a dab of silicone shot into the holes before the screw goes in and have never had a call back.

nealtw

The only time you would have problem with what Joe has suggested is when the perimiter drain isn't doing it's job. For many years now we have had poly under the slab so there would be no problem.

isola96

The slab should be deep enough were the taps or spax won't harm the slab.